T. Joachims, D. Freitag, and T. Mitchell. Proceedings of the International Joint Conference on
Artificial Intelligence (IJCAI), page 770--777. San Francisco, CA, Morgan Kaufmann, (1997)
B. Shaparenko, R. Caruana, J. Gehrke, and T. Joachims. Proceedings of the IEEE ICDM Workshop on Temporal Data Mining: Algorithms, Theory and Applications (TDM-05), page 165--174. (2005)